Lilia Ulanova [1], Einar Mørk [1]

Affiliates

[1] Calpro AS, Norway; www.calpro.no

Abstract

Monitoring of mucosal inflammation makes a pivotal contribution to the therapy of irritable bowel disease (IBD). This requires frequent endoscopic procedures, which are tedious and carry high burden for patients and health services. Therefore, there is a need for an improved non-invasive monitoring method based on a reliable IBD marker, such as calprotectin (CP).
Activation of the intestinal immune system during IBD leads to recruitment of neutrophils. CP comprises 60% of cytosol proteins in these cells, thus the amount of CP is proportional to the number of neutrophils and eventually to the degree of the gut inflammation.
The present study evaluates correlation between routine CalproLab ELISA-based laboratory test for CP and the new point-of-care test (CalproSmart). The latter consists of a feces extraction device prefilled with a buffer, a rapid lateral flow test, a support frame and a smartphone application. The study was performed by trained personnel on both fresh and frozen/thawed stool samples from 50 IBD patients during a 2 weeks period. Upon completion of the study, the operator was asked to fill out a survey evaluating design and user experience with the new test.
The results showed that 93% of the CP values measured by the new CalproSmart and the routine ELISA test were in good agreement with each other. The deviation between the measurements was less than 15% for the majority of the samples (67% of the total) and less than 25% for the rest of them.
In addition, CP values measured by CalproSmart and the routine method were scrutinized for fitting into the correct diagnostic window. This revealed that the tests coincide in 100% of the cases when it comes to measuring samples from acute patients (CP levels above 500 mg/kg), therefore there were no false negative results. CalproSmart and the routine method placed patients with moderate CP levels into the same category in 73% of the cases and healthy individuals – in 86% of the cases.
The new point-of-care CP test, CalproSmart, demonstrated reliability, high degree of accuracy, correlation with the routine test and received a positive feedback on its design and user experience.